I would suggest that they check the temperature sensors - show them the readings, especially the strange ones you’ve had earlier. Additionally I would ask them to check if the unit is correctly connected vs. the left/right version. I.e. that the outside pipe is connected to the correct side of the unit. Consult the manual I’ve linked earlier - in the section 5.1 it describes the way to switch it if needed.
Cool many thanks, will do and let you know.
So basically I need them to check why sensors are not displaying temperatures In the correct way (the picture you draw with names on it).
And having a look at the correct piping in/out.
At this moment that temps are a little chiller this is the situation.
The graphs you now show are normal, its still in “summer mode” but this sun symbol alone doesn’t say much. Not even sure why it has such an indicator. The more important indicator is the bypass symbol (second one counted from the left). If the bypass is active you get cold air into the house to cool the house down after a day when the sun is burning on the house. Although this valve system probably doesn’t get activated because your target is 24C now.
If this unit is already three years there and hasn’t been refurbished / maintained / touched in the last months then I shouldn’t worry too much. However, a quick check if everything is healthy cannot hurt of course. Clean air is important.
With the exception that you can’t get supply (from Comfair to the room) temperature higher than the return (room) temperature. Unless there is some kind of additional heating going on on the pipes e.g. from house heating, kitchen etc. This would suggest to me that the sensor is not calibrated or faulty (assuming that all the connections are correct).
Never seen the bypass symbol on (closed) to be honest also in the past months of the year (I’ve been using this ESP monitoring since Jan 2024).
I’m pretty sure there is no additional heathing or the like in the system.
If the sensor is faulty shouldn’t it just give weird temperatures or not working at all instead of returning “close enough” values?
I understand the calibration part but is it something I can do myself?
I though sensors come already calibrated.
What is the position of your unit, stored somewhere in a dark place? Is foam piping being used or galvanized sheet steel (spiro tubes)?
Maybe the sensors are reporting correctly but there is still some additional external heating taking place without realizing it.
Not sure about the piping material, this is theinternal unit I can access stored in a cabinet with pipes going up into the plasterboard false ceiling.
The unit is installed inside the closed cabinet in a small laundry whth no window.
Amazing work!
I’m planning on buying ERV, seems like Zehnder CA 375 is in good price/performance sweet spot.
I just have one question - is there any core freezing risk while using intake only mode (while using kitchen hood or central vacuum system) ? Because I live in Lithuania and we have some cold winters… Does preheater takes care of that risk automagically?
Thank you in advance
Intake only actually means that exhaust still works but on lower speed. You can’t completely turn of fans in Comfoair units. Obviously if it is freezing cold you should have the preheater installed and it is controlled automatically based on the intake temperature. And it doesn’t depend on if it is in intake mode only or in normal mode.
Do you know exact volume difference between intake and exhaust while “intake only” mode is on?
Because I’m deciding between two ERV’s (Zehnder CA 375 and Renovent Flair 325) and I know that on Flair 325 maximum allowed fan disbalance is 30%, so on max fan speed that would be around 100 m3/h
That depends on your unit volumes and settings. The minimum speed is usually ~15% of max volume. And the intake depends on which speed you are at and what setting for that speed you have configured.
Same what behavior? You have a EWT (geothermal) unit?
Looks fine in my opinion, PVC-U darkblue colored piping/tubes seem to be used. The intake is insolated with mineral wool to prevent condens/waterdrops on the outside of the intake pipe. The unit also has PVC adapters and the Zehnder Comfofoam adapters, I forgot the manufacturer naming of it.
Only questionable part are those supply/return boxes laying right next to each other. I mean those division boxes where the small piping/tubing of the room vents are coming together. These are metal and can transfer temperatures to each other. But if this is an actual problem or a problem at all, I cannot tell because I don’t know. Guess not, the supply temperature is measured far before this point.
I mean that it doesn’t switch to winter
Well… Outside temp. 15.5 I noticed on your screenshot. I finally have HA running, with the “default” wichers comfoair-card.js. This is a bigger temperature difference and I guess it needs to have a bigger temp. difference to get out of summermode. Although summer/wintermode seem to have no effect at all on anything.
Hi, replying almost a year after my last post (#355 of this thread) to give some news : finally, the electronics was still fine. It only needed several hours or days to reset. I guess the time might have been to some condos being discharge, but that seems a very long time. Anyway, this was a great surprise!
Also after letting the installation in manual mode for about a year, I decided to give it another try and it worked like a charm (having made sure that there was no flying wires)! Thanks again @adorobis for this work.
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